It looks as if you won’t get to bring that pocket knife on your next flight after all.

The Transportation Security Administration has delayed a policy change that would have allowed passengers to carry small folding knives onto planes.

In a letter Monday to employees, TSA chief John Pistole said he decided to maintain, at least temporarily, a post-9/11 ban on knives after meeting with an aviation security panel. The policy change allowing knives had been scheduled to take effect Thursday.

Pistole’s letter did not say whether or when he might reconsider lifting the knife ban. Still, he defended easing the ban, saying the bombings at the Boston Marathon underscore the need for TSA to focus on more serious threats such as explosives.

Opponents of allowing knives on planes attributed Pistole’s reversal to “a huge backlash” from flight attendants, airline executives and lawmakers. Since Pistole announced his plans to allow knives, the TSA chief has even been pressured by the families of 9/11 survivors to reconsider.

TSA officials said Pistole made the decision Monday to consider the comments and suggestions of a panel of 27 aviation experts, including airline and airport executives, pilots, flight attendants and families of the victims of the 9/11 terrorist attacks.

“So we can incorporate their input and to continue training requirements nationwide, I have decided to temporarily delay implementing the prohibited items changes,” he said in a letter to TSA workers.

The proposed policy change, announced last month, would have allowed passengers to carry folding knives with blades 2.36 inches or shorter and less than a half-inch wide, as well as pool cues, ski poles, hockey sticks, lacrosse sticks, golf clubs and novelty-size bats.

Until further notice, the items remain banned from the cabins of commercial planes.

According to a survey of about 1,800 Americans released Monday, about 73% said they do not want knives in airplane cabins.

In a statement Monday, a coalition of flight attendants said it would continue to pressure Pistole to keep knives off planes.

“The United States has banned all knives from commercial flights since the September 11, 2001, attacks for good reason: Knives were the terrorists’ weapons of choice in bringing down four jetliners and murdering thousands of Americans,” the group said in a statement.

Congressman Ed Markey (D-Mass), who has spoken out against allowing knives on planes, called the delay “a victory for the passengers, pilots, flight attendants and law enforcement officers who would have immediately been at risk of a knife attack.”

A retired airline pilot who flew commercial planes for 34 years said allowing knives on planes is a bad idea.

“A knife is a weapon, and why make others think we are softening our position?” said Barry Schiff, an aviation safety expert and retired captain for TWA.

Even though pilots are now locked in the cockpit behind metal doors, terrorists could use knives to threaten flight attendants or passengers as a way to force the pilots to open the cockpit doors, Schiff said.

“We’ve done pretty well without knives, and my thought, personally, is to keep them out,” he said.